Microsoft Power BI Power Query and Data Transformation

Question 1

What language does Power Query use for its advanced editor transformations?

Accepted Answer

M language (M formula language)

Answer

Power Query uses M (also called the M formula language or Power Query Formula Language) to define data transformation steps.

Question 2

What does the 'Remove Duplicates' step in Power Query do?

Accepted Answer

Keeps only the first occurrence of each duplicate row based on selected columns

Answer

Remove Duplicates keeps the first occurrence of each unique combination of values in selected columns and removes subsequent duplicate rows.

Question 3

In Power Query, what does 'Unpivot Columns' do to a table?

Accepted Answer

Converts selected column headers and their values into attribute-value rows

Answer

Unpivot transforms wide-format data by turning multiple column headers into an Attribute column and their values into a Value column.

Question 4

What is a 'Query Dependency' in Power Query?

Accepted Answer

A relationship between queries where one query references or is built upon another

Answer

A Query Dependency exists when one Power Query query uses another as its source, creating a dependency chain visible in the Query Dependencies view.

Question 5

Which Power Query step type allows you to combine rows from two tables with the same columns?

Accepted Answer

Append Queries

Answer

Append Queries combines rows from two or more tables with matching column structures, stacking them vertically.

Microsoft Power BI Practice Test